Even if I don't put needles in my mouth (though my husband threatened to put them in my ears while I sleep...), I can understand how the chemical smell/taste would be annoying. When I knit with plastic needles, my hands sometimes smell funny afterwards and I wash them right away. That's one of the reasons that I prefer bamboo.

I never put my needles in my mouth....they have been in many unsanitary places....under airplane seats...between the couch cushions...dropped in the dog food bowl... etc. I do tuck them behind my ear...but NEVER put them in my mouth.

I have swallow casein needles in a variety of pastel colors and some tortoise shell color, too. They do have a chemical type smell if they get wet. I don't put them in my mouth ever, but if I have just put on hand cream and touch the needle, or just washed my hands and not dried them completely, then I smell the chemical smell when I touch those needles. I think it's perfectly normal for casein to smell, so I just don't get these needles wet at all.

I used to tell my sons (when they were small) "Your mouth is not a tool or a third hand! Don't use it that way!". Unfortunately, it was a case of do as I say, not as I do.

I'm always holding a needle in my mouth when I need both hands free...usually when sock knitting as Trish said. And the ONE time I did it with cassien needles was the first and last time I used them. Bryspuns...yuck, ptui, blah![crazy] And that's not just my opinion on the taste... I'd put them behind my ears, but that's like putting something into my cleavage...it just falls right out. My very thin, fine, short hair will not help my floppy ears hold anything.

My theory on putting things in your mouth is like the theory on why it's healthy to let kids pick their noses: you introduce yourself to germs a little at a time, you build up resistance!

I used to sell vintage knitting supplies via eBay and one of the ways to identify old, bakelite knitting needles was by taste. It had a strong, formaldehyde kind of taste, almost numbing to the tonge. I don't know if bakelite is still used to make needles, although I understand it is used once again in costume jewelry, etc. I have also noticed that some writing pens, which sort of end up in the mouth no matter where they've been. also have that same taste.